Blue smoke when cold


5 replies to this topic
  • YZ426F Rider

Posted December 21, 2006 - 09:17 AM

#1

My '02 426 has just started blowing a little bit of blue smoke after I start it. It only blows the smoke when I blip the throttle but not when it is at idle. The bike runs great and once the bike warms up it disappears. The bike does not use oil that I can tell, but then again I change it about every 8 hrs.

Valve guides/seals? If it were the rings then it would smoke all the time wouldn't it?

  • 642MX

Posted December 21, 2006 - 10:19 AM

#2

Have you ever been in the motor?

  • YZ426F Rider

Posted December 21, 2006 - 10:33 AM

#3

Not other than to replace the exhaust cam and check valve clearance. Bought the bike bike used so I don't know how many hours are on it.

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  • 642MX

Posted December 21, 2006 - 10:36 AM

#4

Its probably a valve seal, the valve guides typically never wear. And its definitely time to replace the rings, cam chain, valve springs & valve seals.

  • YZ426F Rider

Posted December 21, 2006 - 10:52 AM

#5

I was planning on doing the timing chain this winter. Never replaced valve components before...is it rocket science or no?

  • 642MX

Posted December 21, 2006 - 12:04 PM

#6

I was planning on doing the timing chain this winter. Never replaced valve components before...is it rocket science or no?


Its not rocket science. You will, however, need a valve spring compressor. You can remove the valve seals with a pick, and reinstall them with your fingers.





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